Optimization of the proportion of multi-component rural solid wastes in mixed composting using a simplex centroid design

• Published in: Bioresource technology 2021-12, Vol.341, p.125746-125746, Article 125746
• Main Authors: Gao, Yi, Tan, Lu, Liu, Fang, Li, Qian, Wei, Xiaocheng, Liu, Liyuan, Li, Houyu, Zheng, Xiangqun, Xu, Yan
• Format: Article
• Language: English
• Subjects: Compost maturity; Multi-component; Response surface methodology; Rural solid wastes
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2021.125746

[Display omitted] •Simplex centroid design was used to optimize four-component mixed composting.•Polynomial equation obtained for the three responses verified to be suitable.•The optimal proportion was 41.4% pig manure, 13.7% human feces and 44.9% rice straw.•Increased kitchen waste had a negative impact on the compost maturity. How to effectively dispose of rural solid waste has become one of the important issues that need to be solved urgently in China. A simplex centroid design was utilized to optimize four-component mixed composting (swine manure, human feces, rice straw and kitchen waste). 24 different runs were conducted to compost based on the mixture design. Three response models (2 special cubic and 1 quadratic) were successfully developed and validated by analysis of variance. It turns out that all models have a very high R2 value ranging from 94.76 to 98.81%. The global solution of the mixture optimization predicted the optimal value of 0.879, in a blend consisting of 41.4% swine manure, 13.7% human feces and 44.9% rice straw. That was considered to be the best combined proportion of mixed composting. This result is instructive for the efficient treatment and resource utilization of solid wastes in rural areas.